Such seat-integrated vehicle occupant restraint systems are housed in the lateral region of the seat rest and in the case of a side impact move between the upper body and the door. The known gas bag modules are integrated into the side face, more precisely into a foamed part of the seat in this region. The seat covering (fabric or leather) has a predefined tear seam by, for example, the seat covering being provided with a slit in a specific region and the slit being sewn, or by two separate sections of the covering adjoining each other in the region of the tear seam and being connected with each other by the tear seam. The different materials of the seat covering which are offered have different extension behaviors. This must be taken into account in the design of the tear seam, because the tear seam is to offer a slight resistance to opening, which resistance is able to be predetermined within narrow limits.
From DE 199 15 831 A1 there is known a seat-integrated vehicle occupant restraint system in which the gas bag module is delimited by a housing made of plastics. The plastics back shell of the seat rest extends across the side wall and covers the gas bag module entirely towards outside. Further, the back shell also extends across an upholstery provided in the region of the side wall, as well as across its seat covering. On inflation of the gas bag the seat covering will not be destroyed, because the outlet opening is formed exclusively in the back shell the edge section of which forms an outwardly swiveling flap.
DE 198 60 312 A1 shows a seat-integrated vehicle occupant restraint system in which a gas bag module having a plastics outer housing is covered by the seat covering. The seat covering is provided with a slit, the opposite edge sections of the seat covering being connected with the outer housing of the gas bag module at various places.
U.S. Pat. No. 5,882,033 and EP 0,826,565 A2 describe seat-integrated restraint systems in which the seat covering comprises two parts in the region of the outlet opening. The outlet opening is closed by a plastics part which is fastened to the edges of the seat covering which are opposite to and spaced from each other. The plastics part works like a flap and forms a whole with the seat covering, i.e. it moves together with the latter.
The invention provides a seat-integrated vehicle occupant restraint system which is distinguished by a cover having a seat covering which independently of its material offers a resistance to tearing which is slight and can be predetermined within narrow limits. Moreover, the gas bag module is to be of simple construction and an opening behavior is to be achieved which is reproducible within narrow limits.